Trimble Business Center

Dave Olander posted 09-21-2022 07:44

I assume this isn't in the US because I can't imagine doing this without some sort of permit, which would likely require some better tie to a datum. I think that you need some sort of a real survey. If I were faced with your situation I would look at the source mapping to determine the datum and go from there.

Mike Hathaway posted 09-21-2022 08:06

I agree with Dave on the ' get it surveyed and tied to the real world'.   You cannot setup a machine grading file in TBC without on-the-ground control points which are on the same coordinate system as your data.  This cannot be done without some surveying. I would regroup entirely or engage someone that has done this before.  This is not something you simply 'do' without training and guidance.

Levi Boward posted 09-21-2022 08:11

This is in th U.S and is perfectly legal and done correctly with no permits for farm ponds under certain acreages. And is by far not the first pond that I have built normal farm or recreational ponds of this size are not designed by engineers it just so happens that these guys are buddies.

my question is I know can go to the site and shoot the property pins with my rover, can I import these in and use these as control points to situate this pond correctly and to get my scale correct.

Dave Olander posted 09-21-2022 08:45

I have to think that you would need to calibrate to points that are either identified or stated in the mapping. Like I said I’d start by looking at the source mapping. Ideally it is tied to a retraceable datum. I don’t see how the property marks help unless they are shown in the mapping and I’d be reluctant to use that to set the scale. My background is using state plane coordinates and navd88 or ngvd29. Those are easy to recover and the scale is defined.

Charlie Sorg posted 09-21-2022 10:26

Levi,

It sounds like this project doesn't have the standard set of survey requirements as a standard construction site given that it's a small farm pond that doesn't require any permits. One option is to set up on the site with your base and rover and create your own control for the project with a one point calibration and shoot in some points you can tie to the PDF. Then you can simply Georeference the PDF in TBC using the control you established and build out your machine control design from there. If you import your Trimble calibration file (.dc or .cal) into TBC, you'll be able to export the whole machine control package for a Trimble enabled machine control in a simple export. It won't be absolutely perfect due to the nature of one point calibrations, but you'll be pretty close especially for a farm pond where the accuracy isn't as crucial as a standard construction site. If you have any further questions on that, I would suggest to enlist the help of your local SITECH for advice and training.

Levi Boward posted 09-23-2022 12:40

Thank you Charlie, your answer seems to be along the lines of what I was thinking. I was plan on going out to this site this weekend and shooting the two property pins and using that to calibrate by site.

In the pdf I have it shows the cross lines of the existing property lines so I believe this will get my close enough ( a couple yards) is really plenty accurate.

I did do a quick test of this lastnight in TBC by just creating to cad points in the corners of the propert line and a rough google earth measurement to scale those two points to the design and it brought my scale way closer to where it needed to be so I believe this will do the trick and with those two points it should position is correctly on the site.